- BRS Bulk GFO Granular Ferric Oxide
Why does BRS recommend this?
Phosphates are going to be one of the biggest battles we have with a reef aquarium. The BRS GFO works great in filter socks and reactors. For the price Standard Granular GFO is going to be one of the best values when it comes to GFO for phosphate removal.
Granular Ferric Oxide (GFO) removes phosphate from the aquarium and is one of the most commonly used filtration medias used in the aquarium industry. GFO is one of the few ways to easily maintain ultra low phosphate on a consistent basis. Maintaining these ultra low levels will help prevent algae outbreaks as well as treat existing algae issues. Your aquariums glass will also stay clear and free of the green hue significantly longer. GFO is most commonly used in a media reactor like the BRS reactor or media bag.
Phosphate inhibits proper coral growth by incorporating itself into the corals skeletal structure which makes it difficult for the coral to grow by laying down additional calcium and carbonate (alkalinity) ions. Maintaining ultra low phosphate levels will increase the growth of any SPS or LPS coral.
Algae outbreaks are one of the most common reasons for a complete tank shut down. We recommend preventing them by maintaining an ultra-low nutrient level environment where it would be difficult for them to get out of control to begin with. It is much easier to prevent outbreaks than it is to treat existing outbreaks.
GFO comes in two types:
- Granular GFO is varied in its shapes and requires the least amount of flow to tumble. Good for reactors.
- High Capacity GFO is twice as dense as Granular GFO, so twice as much material will fit into a reactor. It's extremely hard and has less dust to begin with. Fewer fines will be created during use and transportation. By volume High Capacity GFO will remove roughly twice the phosphate compared to Granular GFO. Best overall performance.
Special note on fighting existing algae problems: Algae needs three main nutrients to grow: phosphate, nitrate and light. Reducing any one of these will significantly slow down algae growth but many not completely solve your issue. Once algae takes hold, it can be a difficult battle but it is winnable. The best offense against algae is to take preventative measures and attack before an outbreak is apparent. Use the following suggestions and be aggressive if an algae problem is already present:
- Maintain undetectable phosphate levels with good feeding habits and use of a phosphate remover like GFO. 99% of all phosphate is added via foods added to the tank.
- Control nitrate levels by reducing feedings, increasing the water change schedule and maintaining a properly sized protein skimmer.
- Use nutrient free RO/DI water for water changes and top off water
- Shorten your lighting period or intensity. In some cases aquarists have found replacing old bulbs that have fallen out of their intended spectrum helps as well
- Continuously remove as much algae as possible by hand.
- Add predators nothing helps an algae outbreak as much as critters who eat it all day long. Various tangs, lawn mower blennies, crabs and snails are all good options. It is also theorized that a healthy pod population will also control algae growth before it gets a chance to take root.
Note: All Bulk GFO is packaged by weight
This product does NOT work in filter socks, it turned my 125 gal tank completely opaque with brown dust. By Zach on 6/20/2018Zach wouldn't recommend this product to a friendI used this product to lower my phosphate levels, but after adding this product to my filter sock my entire tank turned brown/orange. I spent over $130 in salt to clear my tank water and lost a yellow tang, chromis, and a diamond goby pair from the stress it caused on the fish. All of my corals were coated in GFO. They are just beginning to open back up (2 days after water changes) but their is obvious damage to the polyp tips. All in all, I spent $22 on GFO just so that I could force myself to change 200 gallons of water and lose roughly $200 in livestock. This product might work in a reactor but it definitely should NOT be used in a filter sock. There are better, slightly more expensive, products that will work as directed without ruining your entire tank.
Great product By Micah on 6/17/2018Micah would recommend this product to a friendVery clean, works great!
Best way to use your GFO is to use it with Media Reactor By Rick on 4/30/2018Rick would recommend this product to a friendI wanted to share my experience on how to best use this without turning your water in the tank yellow. When I first used this, I used a very fine filter media bag and placed it on the sump. This absolutely got the GFO all over my sump as these are very fine particles and will tumble in the filter media and swirl like a dust and makes a great mess on your tank.
After watching the video here, I bought the carbon reactor and mixed the GFO and Carbon and used the Carbon calculator to makes sure I don't use much. Before running it, I simply pour an RO water on the bottom of the canister like 1/2 gallon of water to rinse out the yellow tint from the GFO. when it was cleared, I installed the reactor and catch the first 1/2 gallon and to my surprise, the water was clean, so I had to pour it back. These stuff works as long that you use the right equipment, otherwise you will scatter the GFO all over your tank. One thing, I put a couple of tablespoon of carbon on top of the mix GFO/Carbon just to stop the GFO leaking on the filter sponge just in case.
No phosphate By John on 3/30/2018John would recommend this product to a friendKeeps phosphate out of my 120 with half the recommended amount
No Good By Me on 3/27/2018Me wouldn't recommend this product to a friendI rinsed and rinsed this product as per the bad reviews. Overnight my filter sock was completely brown. I also noticed that my torch corals were stained brown! I would NOT recommend this product whatsoever. Just stick with Chemi Pure.
Didn't reduce my phosphates at all By Brian on 12/18/2017Brian wouldn't recommend this product to a friendThis product didn't reduce my phosphates even .01. I would not buy this again and do not recommend it.
Great product By Cmac on 12/11/2017Cmac would recommend this product to a friendLove this gfo
Works as described By richard on 10/16/2017richard would recommend this product to a friendWorks as described no issues except it takes a lot of rinsing
Dusty but easy to fix and use By DanG on 9/27/2017DanG would recommend this product to a friendAn effective way of reducing Phosphates. Some advice to those complaining or having fear of dust: As some reviews note, this stuff can be quite dusty. ESPECIALLY at the bottom of the container when you are on the last doses. Having said that, it's very easy to filter out. Simply run water through it in a sock. I shuffle mine back and forth between 2 cups a few times to let the loose dust out first. In MY case, I have an Avast Spyglass so I can put in the media, run water through it to remove particulates, then place in the reactor for use.
My only issue w/this stuff is that it compacts after a week or so and loses the ability to tumble. Hence the 4 stars vs 5. In my case the pros outweigh the cons in spite of the # of cons: Pros - it works. Cons - it only lasts a couple weeks, it's expensive, stops tumbling in my spyglass after a week or so, overuse is a problem.
Sarcastic Disaster By Bork on 9/21/2017Bork wouldn't recommend this product to a friendIf you like looking at a brown tank, then this is the product for you. If you don't like looking at brown tank, but want zero flow coming out of your reactor, then this is the product for you. If you want to drain your entire tank to get the brown water out of your tank, then this is the product for you. If you want to be able to use 20 gallons of water to rinse it out, then this is the product for you* (*actual results may vary with 50 gallons). If you want to look at a tank to look like someone just committed an upper decker (google it), then this is the product for you.
GFO By Joshua on 9/9/2017Joshua would recommend this product to a friendIts GFO it does its job
Great gfo By Bakerrichard27 on 9/1/2017Bakerrichard27 would recommend this product to a friendLong lasting and very effective at removing po4
Starting at: $19.99
Starting at: $44.99
How many cups in a pound of the BRS GFO?
There is 4 cups in our 1lb container, 8 cups in the half gallon/2lb container and 16 cups in a gallon/4lb container.
I want to mix GFO with carbon in the BRS single reactor. Is it OK to use the cheaper GFO to mix in with the carbon or do you need the high capacity GFO? I have a small system so I use low quantities of both carbon and GFO in my reactor. I was just worried about the regular GFO being too small.
It doesn't cause any issues with the reactor to use standard GFO. Really the choice just comes down to the volume of space you have to work with. If you have a large tank you may need more regular GFO then will physically fit in the reactor. Then you either need to get a larger reactor, or use the HC GFO which only requires half the amount.
Sorry I didn't see the instructions, can you tell me how much I will neeed to use in your BRS reactor and how long between changeouts? I have a 90 gal tank and soon to be 125
The easiest way to know is to use the reef calculator at the link below. You just enter the size of your tank and it will tell you how much to run. In the case of your 90g thats about 1.4 cups (22 tablespoons). How long it lasts depends on how much phosphates you add to the tank (which is largely a matter of how much you feed). Pretty typical is 4-6 weeks though.
Hi, can you place the standard GFO in a media bag then place into a media reactor to reduce the fines released into the water.
On 6/22 my phosphorus reading was 3 ppb. On 6/23 reading was 8 ppb, so I started running my BRS GFO reactor. On 6/25 reading was 12 ppb.Today it's 15. Should I change out the gfo? I removed 60 lbs. of sand on 6/20 to reduce nitrate & algae. Thanks
Depending o the changes occurring in the system you may need to change the GFO if the phosphate continues to rise. In systems with more phosphate the GFO will certainly deplete much faster and will need to be changed. Major tank changes can stir up a lot of left over waste which may contribute to the excess levels.
Will this work with a 200 micron filter sock? or will too much be released into the water column? what if GFO gets released into the water? What should be done?
Provided the flow into the sock isn't so strong that it tumbles the media excessively you should be OK. If the media is tumbled to the point where it begins to break up/you notice brown dust on the filter sock, I would use a reactor for the media or place it in a mesh bag in your sump or back chamber of your tank.
The fine particles should not have any negative effects on your fish and coral provided it is only a small amount. There have been anecdotal accounts of a large amount of fine particles having a negative impact but these seem to be limited to extreme cases.
Removal of the fine particles can be achieved with filter socks, filter floss, or any other fine mechanical filtration.
How do you know when it is time to replace the GFO in your reactor?
The best way to know would be to test your water for phosphates using an easy to read phosphate meter like the hanna checker. When phosphates start to increase it would be a sign that the media is depleted and should be changed.
Does your BRS GFO have a shelf life?
I run a 90g tank, I just purchased the dual reactor, and was curious why I can't just put 2 cups in the reactor instead of 1.5 cups.
The recommended amount of GFO is 1.41 in accordance with our instructions and the reef calculator. We recommend running the correct dosage when ever possible as it will limit the impact as well as be much easier to tune and tumble.
How many gph should I run through the GFO for a 40 gallon tank
The GPH through the reactor will need to be set for the volume of GFO so that it has a slight simmer at the top of the GFO in the reactor. If the GFO if not moving it may turn into a brick pretty quickly, or if the tumble is too vigorous then it will end up as as dusty fines from tumbling against itself too hard.
What is the flow requirements of the standard GFO compared to Phosguard?
If my tank is mainly sps dominated would this gfo work well? Or high capacity?
Both will work well on your system! However the High Capacity is more efficient while using less space. The regular will take up more space. Feel free to let us know if you have any further questions!
I am trying to understand how much flow should go through GFO. Should there be enough flow to where the whole column of GFO is slightly tumbling or just enough to where only the surface is tumbling?
There should ideally be enough flow to keep the entire column tumbling to prevent clogging. If clogging occurs try removing some media and adjusting the flow. Feel free to let us know if you have any further questions!
Is GFO the same thing as phosban ? Can it be used in two fishes reactor ? Should it tumble in the reactor? thanks
How much GFO would I need to use in a BRS reactor? I have a 120G display tank with a 40G Sump.
Can I use BRS Bulk GFO Granular Ferric Oxide for freshwater
You can use gfo in both salt and freshwater, it will remove p04 the same.
Is there any aluminum in this? My new toadstool hasn't opened In 3 weeks.
This does not contain aluminum and from our use throughout the years unless overdosed to shock the system GFO does not tend to have a negative impact. Feel free to let us know if you have any further questions!
Does BRS GFO Granular lower alkalinity?
It wouldn't be likely to see any negative effect on your calcium or alkalinity. Its worth noting though, phosphate prevents precipitation (for example the formation of coral skeletons), so by removing phosphates your corals can grow easier which would mean they consume more calcium and alkalinity.
Should GFO be changed just as often as Carbon?
GFO should be changed when it is depleted. How long this takes will depend on the amount of phosphate that is added to the tank. A pretty typical tank that would usually be 4-6 weeks or so but the best way to tell is to monitor the phosphates. When they start to increase that would indicate that DI resin has reached its capacity.
Starting a 90 gallon . will also buy your reactor , how much product do I need to start out to fill the reactor. Thank John
The amount of media depends on the size of your tank with the maximum capacity of the reactor being 2 cups of media, though fortunately with your size tank you wouldn't be in excess of that. For a 90g tank you would use 1.5 cups of media. The easiest way to get measurements for most of these products is to use the BRS Calculator which can be found right here:
I have a biocube 29 and was wondering if this product can be used with some sort of a bag hanging in one of the back chambers of my tank? Will that be effective. I do not have the space or the recources to get a reactor.
It won't be as effective as a reactor and you will want to periodically knead the bag, but it would certainly be better then nothing.
How long should the GFO remain in the reactor? The fake stuff at the stores say 7 hours. Thank you for your time.
It depends on how much phosphates you have. The more you have, the faster it will need to be replaced and vice versa. As a whole though 4-6 weeks would be pretty typical. The best thing to do would be to monitor your phosphate levels with something like a Hanna phosphate checker. When the phosphates begin to rise that would indicate your GFO is used up and its time to change it.